PANG XinMing,
ZHAO MingHui,
LIU SiQing et al
.2019.Seismic phases identification in OBS seismic record sections across the complex geological structure Chinese Journal of Geophysics(in Chinese),62(9): 3482-3491,doi: 10.6038/cjg2019M0452
Seismic phases identification in OBS seismic record sections across the complex geological structure
PANG XinMing1,3, ZHAO MingHui1,3, LIU SiQing2, WANG Qiang1,3, ZHANG HaoYu1,3, REN Yu1,3, QIU XueLin1,3
1. Key Laboratory of Ocean and Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; 2. Guangzhou Marine Geological Survey, Guangzhou 510760, China; 3. University of Chinese Academy of Sciences, Beijing 100049, China
Abstract:Phase identification plays a critical role in modeling the deep velocity structure. The geological structure is complex along the east part of Line T1 across the Gagua Ridge since its topography of sea bottom reaching 3 km in height and the sediment arriving at about 2 km in thickness. As a result, it is difficult to identify seismic phase in Ocean Bottom Seismometer (OBS) seismic record sections. In this paper, we adopt many methods including topographic correction, basement correction, multiple wave identification, forward modeling and travel time projection, and build a set of measures about phase identification for the complex geologic structure taking the OBS data along the east part of Line T1 as examples. The results show that these technical measures of phase identification are useful and effective for OBS data along the complex geological structure, which offers much more accurate travel-time information and obtains more reliable deep velocity structure.
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